Remove odor

Sounds like you have a vent blocked, either on the roof or a vent under one of your sinks.

We had a similar problem first time out this year.
Our toilet dumps straight down into the Black Tank a distance that seems line 24 inches. There appears to be some kind of a flange between the two that `hard stuff' can adhere to. Don't know the purpose of the flange.
We sprayed it with bleach but that just covered up the odor with a nice clean bleach odor but it didn't get rid of the stuff. We finally bought a long skinny brush, like a toilet brush, to wipe it away. Problem seems to be solved.
The next problem is what to do with the brush!

I have owned 5 TT. Only one had a problem with odor. I tried everything I knew to remove the odor. No luck.

I think the the vent stack was installed too deep into the holding tank, but could not prove it without a lot of work.

We learned to live with the odor by running the bathroom fan and putting deodorize in the bathroom

Do you have the roof vent fans running? Ours is pretty tight now and they will suck the entry door closed if it is close. They will definately suck airdown the vent stack and up out of the toilet.

Another question that You need to consider is.. have You changed Your Diet recently Or has anyone started to use some different Meds?

This may seem Odd to You , but certain Foods can cause your Stool and Urine to smell stronger or pungent!

Some Medications also have this effect!

It may be that more Water is needed to dilute the Mix!

Thanks for your replies. I found the problem. A limb had knocked the vent cap askew and covered the vent.
Again thanks for your replies. I found the answer in an odor search.

I use portapotty that has no vent,and adding bit of Javex bleach helps to kill all the odor,,